UA may refer to:

• Unearthed Arcana, a Dungeons & Dragons sourcebook
• Unknown Armies, a tabletop role-playing game
• Urban Assault, a first-person shooter and real-time strategy computer game

• Ua (singer) (born 1972), a Japanese singer-songwriter
• United Abominations, an album by the band Megadeth
• United Artists, a defunct film studio
• The Umbrella Academy, a graphic novel by Gerard Way

• Under Armour, an American clothing brand (NYSE ticker UA)
• Union Association, a baseball league of 1884
• United Airlines, a major American airline headquartered in Chicago, Illinois (IATA airline designator UA)
• United Artists, a film studio
• Universal Audio (company), a designer and manufacturer of audio signal processing hardware and software
• UP Aerospace, a private spaceflight company based in Denver, Colorado

• University Alliance, a lobbying group of British universities
• University of Abra, a public university in Abra, Philippines
• University of Akron, a public research university in Akron, Ohio, United States
• University of Alabama, a public research university located in Tuscaloosa, Alabama, United States
• University of Alaska system, a university system in Alaska created in 1975

• University of Alaska Anchorage, the largest university by enrollment in the system
• University of Alaska Fairbanks, the first university and flagship (known from 1925 to 1975 simply as the University of Alaska)
• University of Alaska Southeast, located in the capital city of Juneau, and the smallest by enrollment

• University of Alicante, a public university in Alicante, Spain
• University of Antwerp, one of the major Belgian universities located in the city of Antwerp
• University of Arizona, a public research university in Tucson, Arizona, United States
• University of Arkansas, a public, co-educational, land-grant, space-grant, research university in Fayetteville, Arkansas, United States

• ultrAslan, a fan group of the Galatasaray Spor Kulübü football team
• United Association, a plumbing and pipefitting labor union in the US and Canada

• Future Force unit of action, a proposed US Army tactical unit
• German submarine UA, a German submarine of the Second World War
• German Type UA submarine, of the First World War
• SM UA, a First World War submarine of Imperial Germany
• Unauthorized absence, a key term for the abandonment of a duty or post without permission (United States)

• ua, ISO country code for Ukraine
• Uttaranchal, a state in India formerly abbreviated as UA in vehicle registration plates
• Upper Arlington, Ohio

• Unstable angina, a type of heart disease
• Uric acid, a metabolic compound
• Urinalysis (also U/A), a set of medical diagnostic tests performed on urine

• .ua, the Internet country code top-level domain for Ukraine
• User agent, a computer networking software class
• User assistance, computer programme manuals and documentation
• Universal Acceptance, a principle regarding top-level domains
• OPC Unified Architecture, a protocol used in industry 4.0 for inter machine communication

• Unmanned aircraft or unmanned aerial vehicle
• Microampere (uA, properly μA), a unit of electric current defined as one-millionth of an ampere
• UA, the product of a heat exchanger's overall heat transfer coefficient U and its active exchange area A in thermodynamics

• Unit of account, in economics, a standard numerical monetary unit of measurement
• Unitary authority, a type of local authority that is responsible for all local government functions within its area
• Urban area or urban agglomeration, a human settlement with high population density and infrastructure of built environment

• U of A (disambiguation)
• Ursuline (disambiguation)